制氢原料中杂质对制氢装置加氢脱硫催化剂的影响

Impact of impurities in hydrogen generation feed on the hydrodesulfurization catalyst of hydrogen generation plant

水蒸气转化制氢,硫是最常见的转化催化剂毒物,因此在进入转化反应之前加ZnO脱硫的效果直接影响制氢装置的正常生产。分析了原料中杂质对脱硫的影响,其中O_2,CO_2,CO等杂质在加氢过程中生成水,从而影响ZnO的脱H_2S的平衡吸收反应,从而对加氢脱硫效果产生影响;氨则破坏加氢催化剂的活性中心,使其有机硫无法转化为无机硫;而铁锈则是生成的金属硫化物,带入转化部分,在转化的条件下还原成硫化氢,使转化催化剂发生硫中毒。实际生产证明,原料加氢脱硫效果好,下游预转化和转化催化剂的活性高,就能保证制氢装置长周期运行,所以应做好炼油厂制氢原料的选择,避免带入以上杂质。

In steam reforming hydrogen generation process, sulfur is one of the detrimental materials of reforming catalyst. Therefore, the performance of ZnO desulfurization before the feed enters the reforming section will have a direct impact on the normal operation of hydrogen generation plant. In the impurities, O2 , CO2 and CO etc will produce water in the process of hydrogenation, affecting the equilibrium adsorption reaction of ZnO to remove H2S and hydrodesulfurization performance. Ammonia will destroy the active site of hydrogenation catalyst, making it impossible for organic sulfur to be converted into inorganic sulfur. Metal rusts are metal sulfides formed in the production. When they are carried over to the reforming section, they will be reduced to H2S under reforming conditions, which will poison the reforming catalysts. The operation shows that a good hydrodesulfurization of feedstock will lead to a higher activity of pre-reforming and reforming catalysts and ensures the long-term operation of hydrogen generation plant. Care shall be taken in the selection of hydrogen generation feeds, and above impurities shall be prevented from entering the unit.